Percutaneous Magnetic Gastrostomy

ABSTRACT

A medical device system includes a needle having a tip including a permanent magnet, and a magnet sensing device including a plurality of sensors configured to detect the magnetic field of the permanent magnet. The magnet sensing device is operable to localize a position of the permanent magnet relative to the magnet sensing device and to indicate a path of the needle on a display.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.12/575,456, filed Oct. 7, 2009, now U.S. Pat. No. 8,437,833, whichclaims the benefit under 35 U.S.C. §119(e) of U.S. Provisional PatentApplication No. 61/103, 419, filed Oct. 7, 2008, each of which isincorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure generally relates to the medical field and moreparticularly but not exclusively relates to the placement of feedingtubes or catheters into the body of a patient.

BACKGROUND INFORMATION

In many medical situations, it is necessary to penetrate the solid orsemi-solid biological matter of the human body at substantially preciselocations. For example, one common medical practice is placement of apercutaneous endoscopic gastrostomy (PEG) tube.

PEG is a procedure used to put a tube into the stomach of a patient whocannot swallow liquids and solids. FIG. 1A illustrates a PEG tube 112 inplace in a human body. In some instances, the tube is instead placedinto the small bowel via a gastrostomy. PEG is used in a wide variety ofcircumstances and generally is effective for helping patients.Traditionally, a PEG tube is placed using endoscopic guidance or x-rayguidance. This step is shown in FIG. 1B. For example, in a traditionalPEG procedure to place a PEG tube into a patient's stomach 100, anendoscope is used to observe that the patient's esophagus is withoutobstruction or diverticulae or for other medical reasons, such as toavoid interference with the pylorus 102. An endoscope is also used toinspect the stomach and inflate the stomach to see that the areaselected for the gastrostomy can be distended. In this manner, a medicalpractitioner (who may be an endoscopist) uses an endoscope to select anarea of the lower body of the stomach or antrum (the gastric wall) thatis particularly suitable for the PEG tube placement. This step is shownin FIG. 1C.

In another step of the traditional placement of a PEG tube procedure,the endoscopist shines the endoscopic light out from the gastric lumenin a darkened room so that a second medical practitioner (who may be anyperson trained in such medical procedures) can see the light andidentify that it is in a reasonable location of the patient's body,e.g., not above the ribs. FIG. 2 shows how an endoscopic light may beseen to varying degree through the skin of a patient.

FIG. 3 shows another step in the traditional placement of a PEG tube inwhich the endoscopist will watch the second medical practitioner push afinger into the stomach wall and hopefully see the indentation 104 inthe area selected by the endoscopist for the PEG tube placement.

FIG. 4A shows another step in the procedure of placing a PEG tube. Ifthe location of the indentation is suitable, and especially if theindentation is clear, this spot is selected. The assistant then makes asmall incision in the skin and inserts a needle 106 into the patient inthe area in which the endoscope's light was seen.

FIG. 4B shows another step in the traditional placement of a PEG tube inwhich the endoscopist will watch a needle 106 as it is pushed throughthe patient's skin and then through the abdominal wall, and theendoscopist will watch the needle tip enter the stomach in the selectedarea.

FIG. 5 shows another step in the traditional placement of a PEG tube inwhich the endoscopist will see a wire 108 pass through the needle 106into the gastric lumen.

FIG. 6 shows another step in the traditional placement of a PEG tube inwhich the endoscopist will use an endoscopic snare 110 to grasp the wire108 firmly. The endoscopist uses the snare 110, passed through thebiopsy channel of the endoscope, to firmly grab the wire 108. Theendoscope and snare 110 are then withdrawn via the patient's mouth,thereby pulling the wire 108 with it. The part of the wire 108 thatextends out from the patient's mouth is subsequently attached to a PEGtube.

FIG. 7 shows another step in the traditional placement of a PEG tube inwhich the endoscopist has withdrawn the entire endoscope, including thesnare 110 holding the wire 108 that was passed through the needle 106,and the wire that passes through the needle extends out of the patient'smouth.

Once the wire 108 is successfully passed through the patient, a PEG tube112 is secured to the end of the wire extending from the patient'smouth. The PEG tube 112 is guided into the patient's mouth and pulledinto the patient's stomach 100 as the wire 108 is pulled from the endthat passed through the needle 106. Once the PEG tube 112 is in thestomach, it is pulled partially through the gastric and abdominal wallsuntil the bumper of the PEG tube is snug against the gastric mucosa.

FIG. 8A shows another step in the traditional placement of a PEG tube112 in which an endoscope is again passed into a patient andsubsequently used to visually observe that the bumper of the PEG tube112 is snug against the gastric mucosa.

In other traditional PEG tube placement procedures, endoscopy is notused at all. Instead, x-ray is used to help select a particularlysuitable location in the patient's body (e.g., the stomach) for theintroduction of the PEG tube. X-ray is used for guiding the PEG tubeplacement and for inspecting the PEG tube's final position.

BRIEF SUMMARY

The present embodiments address several problems of traditional PEGplacement by using new procedures and devices for placement of medicalequipment.

One aspect provides an apparatus that includes a flexible piece ofmedical tubing having a proximal end and a distal end, an elementaffixed to the distal end, the element having ferromagnetic properties,and a first lumen extending lengthwise through the flexible tube, thelumen configured to pass matter into the patient.

Another aspect provides a system for placing a medical device through apatient having medical tube means for passing matter into the patient,ferromagnetic means affixed to a distal end of the medical tube meansfor identifying a substantially precise location of the distal end,detection means for locating the distal end of the medical tube means,means for passing a medical wire between a first location occupied bythe detection means and a second location occupied by the ferromagneticmeans, and means for attaching the medical device to the medical wire.

Another aspect provides an endoscopic-like controllable guide tubeapparatus having a flexible tube free of optics, suction, irrigation,and light sources, a channel configured to pass a magnetic tippedmedical device, and a control operative to orient a distal end of theflexible tube.

Another aspect provides a magnetic nasogastric tube apparatus having aflexible tube having a proximal end and a distal end, wherein theflexible tube is torsionally rigid, an element affixed to the distalend, the element having ferromagnetic properties, and at least oneindicator located near the proximal end operative to communicate theorientation of the distal end relative to the indicator.

Another aspect provides a magnetic gastrostomy placement tube apparatushaving a torsionally rigid flexible tube having a proximal end and adistal end, an element affixed to the distal end, the element havingferromagnetic properties, at least one indicator located near theproximal end of the torsionally rigid flexible tube, the indicatoroperative to communicate an orientation of the distal end relative tothe indicator, a channel formed lengthwise along the torsionally rigidflexible tube, the channel operative to pass a guide wire, and an outersurface of the magnetic gastrostomy placement tube configured to besterilizable.

Another aspect provides a method for placing a magnetic nasogastric tubeinto a patient having the steps of verifying that the patient'sesophagus is unobstructed, placing a distal end of the magneticnasogastric tube into the patient's mouth, advancing the magneticnasogastric tube down the patient's throat, advancing the magneticnasogastric tube through the patient's esophagus; and advancing themagnetic nasogastric tube into the patient's stomach.

Another aspect provides a method of selecting a location on a patient'sbody for placing a percutaneous gastrostomy tube having the steps ofadvancing a magnetic nasogastric tube into a patient, locating a distalend of the magnetic nasogastric tube with a magnetic detection sensordevice, and positioning the distal end of the magnetic nasogastric tubeinto a desirable area by manipulating a proximal end of the magneticnasogastric tube.

Another aspect provides a method of placing a medical device into apatient's body having the steps of advancing a magnetic nasogastric tubeinto a patient's stomach, locating a distal end of the magneticnasogastric tube with a magnetic detection sensor device, positioningthe distal end of the magnetic nasogastric tube into a desirable area bymanipulating a proximal end of the magnetic nasogastric tube, distendingthe patient's stomach by passing a gas through the magnetic nasogastrictube, passing a needle through the patient's abdominal wall at about thedesirable area, passing a medical wire through the patient's abdominalwall, and using the medical wire to position the medical device into thepatient's body.

Another aspect provides a method for using an endoscopic-likecontrollable guide tube having the steps of passing a flexible tubeconfigured on the endoscopic-like controllable guide tube through themouth of a patient and into the patient's stomach and passing a magneticnasogastrostomy tube down a channel in the endoscopic-like controllableguide tube.

Another aspect provides a method for installing a percutaneousgastrostomy tube having the steps of passing a magnetic nasogastrostomytube into the stomach of a patient, verifying that the gastric cavityallows a distal end of the magnetic nasogastrostomy tube to move freely,pressing the distal end of the magnetic nasogastrostomy tube against thepatient's gastric wall, placing a magnetic detection sensor deviceagainst the patient's abdominal skin, detecting the distal end of themagnetic nasogastrostomy tube with the magnetic detection sensor device,and placing the percutaneous gastrostomy tube through the patient'sabdominal wall toward the distal end of the magnetic nasogastrostomytube.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments are described with referenceto the following drawings, wherein like labels refer to like partsthroughout the various views unless otherwise specified. The sizes andrelative positions of elements in the drawings are not necessarily drawnto scale. For example, the shapes of various elements and angles are notdrawn to scale, and some of these elements are arbitrarily enlarged andpositioned to improve drawing legibility. Further, the particular shapesof the elements as drawn, are not intended to convey any informationregarding the actual shape of the particular elements, and have beensolely selected for ease of recognition in the drawings. One or moreembodiments are described hereinafter with reference to the accompanyingdrawings in which:

FIG. 1A illustrates a PEG tube in place in a human body.

FIG. 1B shows an endoscope is used to inflate the stomach and select anarea for the PEG tube according to the prior art;

FIG. 1C shows, the view an endoscopist sees when looking at the stomachwall;

FIG. 2 shows the light of the endoscope is seen to varying degree on theskin of the patient according to the prior art;

FIG. 3 shows the indentation of the second operator's finger as seen byan endoscopist according to the prior art;

FIG. 4A shows a needle inserted into the patient via a small incision inthe area in which the light of the endoscope was seen;

FIG. 4B shows the tip of a needle entering the stomach as seen by anendoscopist according to the prior art;

FIG. 5 shows a medical wire entering the stomach through a needle asseen by an endoscopist according to the prior art;

FIG. 6 shows a snare, passed via the endoscope, grasping the medicalwire according to the prior art;

FIG. 7 shows the snare holding the medical wire is pulled out of thepatient according to the prior art;

FIG. 8A shows the bumper of a PEG tube against the gastric wall as seenby an endoscopist according to the prior art;

FIG. 8B shows a circumstance where the light from an endoscope shiningon the abdominal wall is vaguely seen;

FIG. 8C shows the view an endoscopist sees if the indentation is broadand not clear when seen from the gastric side;

FIG. 8D shows a needle that has missed the stomach, gone deep into thepatient, and put the patient in danger of an injured adjacent organ;

FIG. 9 shows a nasogastric (NG) tube with a magnet is passed into thestomach according to an embodiment;

FIG. 10A shows a magnetic detection sensor device “seeing” the magnet inthe stomach and assuring that the tip of the tube is actually below theribs and most likely in the stomach according to an embodiment;

FIG. 10B shows a sensing device covered with a sheath in accordance withone embodiment;

FIG. 11A shows a magnetic detection sensor device locating the magnetand giving a substantially precise distance according to an embodiment;

FIG. 11B shows an image on a magnet sensing device, where X and Y arenoted as well as Z, depth, along with the direction of a magnet inaccordance with one embodiment;

FIG. 11C shows a target guide on a sensing device's screen along withthe depth to the magnet in accordance with one embodiment;

FIG. 12 shows a balloon inflating around or behind the magnet on themagnetic nasogastric tube according to an embodiment;

FIG. 13 shows the operator “seeing” the magnet regardless of whether ornot the magnet is inside a balloon, and if the magnet is inside theballoon, the operator knows and can compensate appropriately fordistances according to an embodiment;

FIG. 14A shows the needle guide directing the needle to the magnet onthe magnetic nasogastric tube with substantial precision according to anembodiment;

FIG. 14B shows a ring of lights of appropriate frequency and sufficientintensity to penetrate the skin and abdomen and to be readily seen onthe inside of the patient by the endoscopist, on the bottom of a sensingdevice along with a guide channel through the ring used to guide theneedle insertion in accordance with one embodiment;

FIG. 14C shows a situation where the endoscopist clearly sees the lightfrom the ring of lights on the bottom of a sensing device in the areatargeted for needle placement in accordance with one embodiment;

FIG. 14D shows a screen on a sensing device indicating position anddepth of a magnet, and the sensing device has a target guide for theguide path of the needle to inform the operator that if the needle isplaced into the guide channel and advanced via the guide channel, theneedle tip will approach the magnet in accordance with one embodiment;

FIG. 15 shows the needle inserted to the measured distance as determinedby the magnetic detector according to an embodiment;

FIG. 16 shows a medical wire with a magnet on the tip is insertedthrough the needle close to the magnet on the magnetic nasogastric tubeaccording to an embodiment;

FIG. 17 shows the two magnets sticking together according to anembodiment;

FIG. 18 shows an electric current facilitating a determination that thetwo magnets are touching according to an embodiment;

FIG. 19 shows a magnet-to-magnet junction being removed from the patientthrough the nasogastric tube or with the magnetic nasogastric tubeaccording to an embodiment;

FIG. 20A shows that correct force is being used to pull the PEG tube upagainst the gastric mucosa, and the PEG tube is being secured in placeaccording to an embodiment;

FIG. 20B shows that the bumper looks snug endoscopically, but thegastric mucosa is not up against the abdominal wall according to anembodiment;

FIG. 21 shows the magnetic nasogastric tube placed into the stomach,inflating the stomach with a balloon on the tip, and the magnet ispushed against the gastric wall according to an embodiment;

FIG. 22 shows the magnetic detection sensor device determining thedistance and location of the magnet on the tip of the magneticnasogastric tube according to an embodiment;

FIG. 23 shows a needle being passed towards the magnet on the magneticnasogastric tube by using information presented on the magnetic sensordevice according to one or more embodiments; in one embodiment a bombsite is used to direct the tip; in another embodiment, a needle guide isused to assure the path of the needle to the magnet; in each embodiment,the direction and the distance is known from the magnetic sensor device;

FIG. 24 shows an introducer being passed over the needle or over a wirepassed via the needle according to an embodiment;

FIG. 25 shows the gastrostomy tube being passed over the introduceraccording to an embodiment;

FIG. 26 shows the wire or needle and the introducer being backed out,and the gastrostomy tube left in place after a strain gauge was used tomeasure pull back force to assure that the bumper was snug according toan embodiment;

FIG. 27 shows the bumper being compressed and stretched as it isintroduced, and once in the gastric lumen, it is released and reassumesits shape as a bumper according to an embodiment;

FIG. 28 shows the gastrostomy tube with the stretched bumper beingpassed down the lumen of the introducer; and after advancing into thestomach, the “stretch” is relaxed, and the bumper forms its shape andcan be pulled upon to snugly come up against the gastric mucosaaccording to an embodiment;

FIG. 29 shows a magnetic nasogastric (MNG) tube is being passed into thestomach according to an embodiment;

FIG. 30 shows the magnetic detector being placed over the left upperquadrant (LUQ) in a spot suitable for a gastrostomy to exit the skin ofthe abdominal wall according to an embodiment;

FIG. 31 shows the stomach being inflated via a channel of the magneticnasogastric tube according to an embodiment;

FIG. 32 shows the magnetic detector locating the magnet and determiningits orientation and distance to the skin according to an embodiment;

FIG. 33 shows the magnetic nasogastric tube having a balloon, which canbe inflated to determine that the area of the magnet is distensiblefreely; low pressure inflation is used to prevent injury and to be surethat inflation is easy at low pressure according to an embodiment;

FIG. 34 shows a plunger being used to advance the needle towards themagnetic detection sensor device according to an embodiment;

FIG. 35 shows the magnet on the tip of the needle being watched as itmoves towards the magnetic sensor according to an embodiment;

FIG. 36 shows the sharp tip of the needle is covered, and the needlebeing pulled away from the skin pulling more of the medical wire behindthe needle with it according to an embodiment;

FIG. 37 shows the plunger and covering tube of the magnetic nasogastrictube (with the deflated balloon if the catheter has a balloon) beingremoved leaving the wire that was used to push the needle according toan embodiment;

FIG. 38 shows the wire attached to the tapered tip of the gastrostomytube according to an embodiment;

FIG. 39 shows the tapered end of the gastrostomy tube being passed intothe stomach over the wire and allowing the wire to act like a guide wirewhen the gastrostomy tube is pushed using a pusher tube according to anembodiment;

FIG. 40 shows the gastrostomy tube being pulled into position and astrain gauge used to measure a suitable amount of pulling force on thegastrostomy tube to assure a snug fit according to an embodiment;

FIG. 41 shows the pusher tube being removed with the guide wire when thegastrostomy is in place according to an embodiment;

FIG. 42 shows a balloon orienting the tip of the magnetic nasogastrictube according to an embodiment;

FIG. 43 shows a tripod opening to orient the tip of the magneticnasogastric catheter according to an embodiment;

FIG. 44 shows controllable guide wires bending the tip of a magneticnasogastric tube in the desired direction; torque stability allows theorientation of the tip of the magnetic nasogastric tube to be controlledby rotating the tube at the patient's mouth according to an embodiment;

FIG. 45 shows the magnetic nasogastric tube is not “floppy” but can besufficiently stiff to allow passage of the needle and wire according toan embodiment;

FIG. 46 shows an endoscope directing the tip of the needle in thedesired direction and providing the stiffness needed to advance theneedle; the endoscope can select the site on the mucosa of the stomach(guided by the magnetic sensor on the outside; and the endoscope canalso be pushed against the mucosa to facilitate passage of the needleaccording to an embodiment;

FIG. 47 shows an embodiment of a guide tube;

FIG. 48 shows a large balloon stabilizing the tube tip by filling up thestomach transiently until a needle is passed according to an embodiment;

FIG. 49 shows a balloon with an internal structure to assure uniforminflation according to an embodiment;

FIG. 50 shows that the guide tube is flexible, but when in position,wires are pulled and the guide tube guiding the magnetic nasogastrictube, magnet, and needle for insertion becomes stiff to facilitatekeeping the magnetic nasogastric tube in position, which helps passageof the needle according to an embodiment;

FIG. 51 shows a soft introducer tip for a controllable magneticnasogastric tube having a groove for a guide wire and a magneticnasogastric tube having a channel for a guide wire according to anembodiment;

FIG. 52 shows bending the tip of the controllable magnetic nasogastrictube with a control handle; one direction may be all that is used as thetorque stability makes the tip bending go in any direction according toan embodiment;

FIG. 53 shows a slide plunger attached to the guide wire for advancing aneedle and the plunger can then be released according to an embodiment;

FIG. 54 shows an airport and an insufflation system according to anembodiment wherein a pump, syringe, or bag can be used to inflate thestomach, and a valve for preventing over distension may also be used;

FIG. 55 shows a magnetic nasogastric tube with a soft tip for ease ofintroduction wherein the tip is softer and more flexible than is theshaft of the magnetic nasogastric tube according to an embodiment; and

FIG. 56 shows a magnetic element in the tip of the magnetic nasogastrictube or in the tip of the soft flexible introducer according to anembodiment;

FIG. 57 shows an area of the gastric mucosa suited for PEG placement isidentified and a catheter placed onto the area in accordance with oneembodiment;

FIG. 58 shows a detector used to locate the position of a magnet on thetip of an endoscopic catheter in accordance with one embodiment;

FIG. 59 shows palpation used to show that the location of an externalsite is close to the intraluminal site in accordance with oneembodiment;

FIG. 60 shows a needle pushed through the gastric mucosa by advancing acatheter in an endoscope channel; this may be with the endoscope rightagainst the gastric mucosa or with the endoscope back a distance fromthe mucosa in accordance with one embodiment;

FIG. 61 shows that a needle may rotate to facilitate cutting as it exitsthe gastric lumen in accordance with one embodiment;

FIG. 62 shows a needle is enclosed inside the tip of a catheter until itis time to deploy; where the tip of the catheter is then pulled back(shortened) thereby stabilizing the catheter tip and widening the tipthen allowing the tip of the needle catheter inside to exit inaccordance with one embodiment;

FIG. 63 shows a needle is inside an endoscopic catheter and exits whenpushed at the proximal (outside) end of the catheter in accordance withone embodiment;

FIG. 64 shows how a magnet on the tip of a needle is seen inthree-dimensional space by a detector enabling an examiner to see wherethe needle is moving as it is advanced from the gastric lumen to theoutside in accordance with one embodiment;

FIG. 65 shows a wire removed from an endoscope channel and attached tothe tip of a PEG tube in accordance with one embodiment;

FIG. 66 shows a wire out of a patient's mouth attached to a PEG tube andpulled via the mouth into position on the skin of the anterior abdominalwall in accordance with one embodiment;

FIG. 67 shows a colonoscope placing a magnet, which is used to place atube through the skin into the colon where desired in accordance withone embodiment;

FIG. 68 shows a cystosomy tube placement into the bladder in accordancewith one embodiment;

FIG. 69 shows a magnet directed laparoscopically to select a spot for asecond penetration, and the area is detected from the outside using thesensing device in accordance with one embodiment;

FIG. 70 shows a magnet passed intravascularly into an area using x-rayguidance, the magnet is located using a sensing device, and a diagnosticor therapeutic catheter is guided to the magnet placed at a target(e.g., tumor, etc.) in accordance with one embodiment;

FIG. 71 shows a screen on a sensing device giving the substantiallyprecise location of a magnet on a catheter, the depth, the direction anda guide path for a device when inserted into the guide channel of thesensing device in accordance with one embodiment;

FIG. 72 shows a catheter placed under guidance (e.g., x-ray, CT, MRI orultrasound) into a target tumor, and the detector detects a magnet anddirects therapy to the target with a guide path, including depth inaccordance with one embodiment; and

FIG. 73 shows a sensing device with a mechanism to release the needle orwire from the guide channel.

DETAILED DESCRIPTION

Traditional PEG placement procedures are imperfect, costly, and havemany problems. For example, in some situations the endoscope's light isnot clear on the abdominal wall. This is especially a problem if thepatient is obese with a thick abdominal wall or if organs are betweenthe stomach wall and the anterior abdominal wall (e.g., liver, colon,etc.). Using the endoscopic light to locate a suitable area of thegastric wall is very difficult in some patients, which is a problem noteasily solved with current procedures or equipment.

Another example where problems occur with current procedures andequipment is if the patient is obese or if the location is not ideal. Inthis situation, the indentation made by the medical practitionerpressing against the abdomen from the outside is not clear to theendoscopist. Instead, a vague area moves in response to the outsidepractitioner's finger. A thick wall, intervening organs, or poorpositioning may cause the vague indentation or motion. The indentationmay be hard to see endoscopically and in some cases, is a problematicway to determine where the needle will enter the stomach.

Another example of a problem with current procedures and medical devicesoccurs because the medical practitioners have very little informationabout the target. The practitioner only knows to insert the needle wherethe endoscopic light was seen. The practitioner neither knows thedirection to advance the needle nor the depth of the stomach wall. Forthis reason, the needle may be inserted and pushed a considerable depthinto the patient before the endoscopist and/or assisting medicalpractitioner realize that the position is not ideal. The needle maycause injury to the patient when it is deeply advanced and/or advancedmultiple times in the wrong direction to the wrong depth.

FIG. 8B, for example, shows a situation where the endoscope's light isnot clear on the abdominal wall. This is especially a problem if thepatient is obese with a thick abdominal wall or if organs are betweenthe stomach wall and the anterior abdominal wall (e.g., liver or colon).Using this light to locate the selected area of gastric wall is verydifficult in some patients, which is a problem that is difficult tosolve with current procedures or equipment.

FIG. 8C, for example, shows another situation where problems occur withcurrent procedures and equipment. If the patient is obese or if thelocation is not suitable, the indentation made by the assistant pressingagainst the abdomen with a finger 104 from the outside is not clear tothe endoscopist. Instead, a vague area moves in response to the outsideexaminer's finger 104. A thick wall, intervening organs or poorpositioning may cause the vague indentation or motion. The indentationmay be hard to see and in some cases, is a problematic way to determinewhere the needle will enter the stomach.

FIG. 8D shows another example of the type of problem that may occur withcurrent procedures and medical devices. The assistant has very littleinformation about the target. The assistant only knows to insert theneedle 106 where the endoscope light was seen. The assistant neitherknows the direction to advance the needle 106 nor the depth of thestomach wall. For this reason, the needle 106 may be inserted and pusheda considerable depth into the patient before the endoscopist and/ormedical assistant realize that the position is not suitable. The needle106 may cause injury to structures or adjacent organs when it is deeplyadvanced and/or advanced multiple times in the wrong direction to thewrong depth. In fact, it is common to limit the number of passages ofthe needle 106 to four passes.

Another example of a problem with traditional PEG placement proceduresis that the procedures are implemented with costly medical equipmentthat is also relatively large and immobile. Both endoscopes and x-raymachines typically require large power supply systems and their use isnot readily compatible with harsh physical environments. The expense,size, fragility, power requirements, and other limitations means that insome clinical areas, such as in less developed areas, nursing homes, orchronic care facilities, or in emergency situations, or battlefield ormilitary aid station, for example, neither endoscopy nor x-ray isavailable, and the result is that traditional PEG procedures cannot beperformed.

The problems described herein, and many others, may result in theinability to perform a PEG procedure because traditional medicalequipment is unavailable. Further, even when the equipment is available,current procedures may result in perforation or other injury of anadjacent organ (for example the colon or liver), or may require multipleinsertions, causing pain and trauma to the patient. Another problem isthat the procedure may fail to successfully place the PEG tube at all.The current PEG placement procedure and devices have low precision andoffer only minimal guidance, especially when the patient is not thin.The minimal guidance is very crude and depends both on the patient'shabitus (thin is better for localization) and the medical practitioner'sexperience and judgment.

According to principles of the present invention, new tools andtechniques are provided for integration with a living body as will nowbe described. These new techniques provides a unique way to preciselydetermine the location, direction, and depth of the selected site on thegastric wall without the use of endoscopic or x-ray equipment. Theyallow practitioners to have a higher assurance of the location of thesite of penetration into the stomach of the needle and subsequent wirefor the PEG tube.

A new alternative to PEG tube placement is presented herein and whichcan be called Percutaneous Magnetic Gastrostomy (PMG). PercutaneousMagnetic Gastrostomy does not require endoscopy or x-ray and thereforecan be less expensive and can be performed in clinical areas in whichneither endoscopy nor x-ray is available.

In the new gastrostomy procedures described herein and shown in theassociated figures, no x-ray is used, and no endoscopy is necessary. Theprocedures are fast and guided safely by the presence of the magneticelement on the tip of the device passed into the patient's body. Theequipment and procedures may be used in hospitals and may also be usedin alternative sites such as a nursing home or in places which do nothave x-ray or endoscopy. The gastrostomy equipment and procedures may beused wherever there is an acute need to get fluid and electrolytes intoa patient who cannot swallow. Some examples where this equipment andprocedures may be used are after trauma, in a third world location orsimilar environment in which there is simply not enough IV fluid, or ona battlefield to support the intravascular volume of an injured person.Rather than relying on IV s, the equipment and procedures disclosed usethe patient's GI tract to rapidly absorb fluid, electrolytes andnutrients.

For example, in some situations, the small bowel is functioning normallyand can readily absorb water, electrolytes, and nutrients (e.g.,protein, carbohydrates, lipids) plus medications especially if modifiedwith molecular chaperones to move rapidly into the patient via the smallbowel mucosa. It may be possible to support a person in this way usingnon sterile fluids, electrolytes, and nutrients just as in normal food.Passing the fluids and electrolytes directly into the stomach via thegastrostomy tube has several advantages. For example, the fluid andnutrients need not be sterile, but instead can be food and water thatone would drink. Also, a large volume can be passed using the stomach asa reservoir, and the speed of absorption of a fluid and electrolytemixture introduced into the stomach may exceed that of an IV. Further,use of easily absorbed molecules or molecular chaperones may allowmedications such as antibiotics to be absorbed from the small bowel veryrapidly. This may be essential in a place where the IV solution of themedications is not available. It may be less expensive, and it may allowuse of intragastrically delivered (e.g., to the GI tract) medicationsand does not limit the patient to IV medications only.

On the other hand these fluids and nutrients would not be tolerated ifthe material was given IV. This could be very important in a poorcountry or in trauma, or in other situations where IV fluid with sterilecomponents may not be available in a suitable quantity.

In the following description, numerous specific details are given toprovide a thorough understanding of embodiments. The invention can bepracticed without one or more of the specific details, or with othermethods, components, materials, etc., that are equivalent. In someinstances, well-known structures, materials, or operations are not shownor described in detail to avoid obscuring aspects of the invention.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. Thus, the appearances of the phrases “in oneembodiment” or “in an embodiment” in various places throughout thisspecification are not necessarily all referring to the same embodiment.Furthermore, the particular features, structures, or characteristics maybe combined in any suitable manner in one or more embodiments.

The headings provided herein are for convenience only and do notinterpret the scope or meaning of the embodiments.

In the embodiments and descriptions disclosed in the text and figures ofthe specification, several terms are used, including but not limited to,“magnet,” “magnetic element,” and elements or components having“magnetic properties.”

Those skilled in the art will recognize that the specific terms arenon-limiting and include hard or permanent magnets, soft magnets,electromagnets, and other material compositions having ferromagneticproperties. For example, the description of an element as a “magnet” mayindicate that the element has or is constructed from a permanent magnet,a ferrous metal, or any other material having ferromagnetic properties.

A. Using a Magnetic Nasogastric Tube to Place a Peg Tube

One or more embodiments of the new approach to percutaneous gastrostomyare illustrated in FIGS. 9-20A and described in detail by way ofnon-limiting and non-exhaustive examples. FIG. 9 shows elements of afirst example. A new type of nasogastric (NG) tube, a magneticnasogastric (MNG) tube/catheter 114, is placed into the patient's mouthand gently advanced down into the stomach. Additional embodiments of thenew type of nasogastric tube will be described later in this section.

Prior to inserting a tube down a patient's throat, the medicalpractitioner must have a degree of confidence that the esophagus isopen. In the new approach to tube placement described herein, thepractitioner may note that frequently, a patient with an abnormalesophagus will have symptoms of dysphagia. Also many of these patientswill have been endoscoped recently or had an upper GI x-ray for theirmedical problem. Either will determine if the esophagus is abnormal. Ifthere are symptoms or evidence of an abnormal esophagus, an endoscopy orx-ray should precede the Percutaneous Magnetic Gastrostomy procedure or,alternatively, a traditional PEG procedure may be performed. Ease ofpassage of the magnetic nasogastric tube is further evidence of a patentesophagus.

In example embodiments, the magnetic nasogastric tube 114 has a magnet116 on the tip. In some embodiments, the magnetic nasogastric tube 114has a ferrous metal element or a mass of ferrous material secured at aknown location The encapsulated magnet 116 may be a permanent magnetformed from any number of magnetic materials, including but not limitedto AlNiCo, SmCo, and NdFeB types. The permanent magnet may be formed bya variety of process including but not limited to forming alloys,sintering of magnetic powders, and embedding magnetic powders withinanother binder material. The encapsulated magnet may also be anelectromagnet, in which the magnetic field is generated by a steady oran alternating electric current passing through a wire coil of some sizeand shape, and in which the wire coil may surround a core ofmagnetically permeable material. The encapsulated magnet may also be acombination of a permanent magnet and electromagnet.

When the desired length is passed (for instance approximately 50 cm fora typical adult patient), FIG. 10A shows a magnetic detection sensordevice 118 is placed onto the abdominal wall to look for the magnet.FIG. 10B shows an embodiment of a magnetic detection sensor device 118.The magnetic detection sensor device 118 may also be referred to as a“magnetic sensing device,” “sensing device,” “sensor device,”“detector,” or the like.

A disposable or reusable sterile sheath 120 covers the sensing device toprevent contamination with the placement of the needle 106 and wire 108.The sensing device 118 is placed on the patient's abdominal wall. Thesensing device 118 can readily locate the magnet 116 on the tip of themagnetic nasogastric tube 114. In some embodiments, an audibleindication informs the examiner of the position of the magnet 116. Inother embodiments, a display is used in cooperation with an audibleindicator or a display is used by itself. Additional examples oftechniques that may be used by the magnetic detection sensor device todetermine the location and orientation of magnets are disclosed in U.S.Pat. Nos. 5,879,297, 6,129,668, 6,216,028, and 6,263,230. The medicalpractitioners that are operating the magnetic nasogastric tube and themagnetic detection sensor device may choose an area that is particularlysuitable for the Percutaneous Magnetic Gastrostomy tube by rotating themagnetic nasogastric tube and by moving the sensor device until themagnet is “seen” in the desired area. The magnetic detection sensordevice, as shown in FIG. 11A, can then determine the distance from theskin to the magnet.

For example, FIG. 11B shows the X and Y position noted on ahigh-resolution or other suitable display screen 122 that may beintegrated with the sensing device 118 or coupled to the sensing device118.

An example layout of the display screen 122 can be in the form of target“crosshairs.” The distance from the sensing device on the patient's skinto the magnet (i.e., the depth, or Z position) is determined withsubstantial precision and also shown on the screen 122. In addition, thedirection from the skin to the magnet 116 is known and can be displayedon the screen 122 as a target guide. For example, and as represented inFIG. 11C, the sensing device 118 can be repositioned along the outersurface of the stomach of the patient, until the target magnet 116 iscentered in the crosshairs of the screen 122.

In some embodiments, once the position and depth of the desired locationon the magnetic nasogastric tube 114 is determined, a balloon may beinflated in the stomach 100. FIG. 12 shows a balloon 124 inflatingaround or behind the magnet on the magnetic nasogastric tube 114according to an embodiment. In other embodiments, the stomach isinflated without a balloon. The distensibility of the antrum isevaluated in embodiments of the percutaneous magnetic gastrostomyapproach by knowing that the balloon or stomach cavity will inflate toan appropriate volume, e.g., approximately 300 cc for a typical adultpatient. This may demonstrate that the magnetic nasogastric tube 114 isin the stomach as other areas (e.g., the small bowel) will not gentlydistend when the area is inflated. In some embodiments, a pressure valveprevents high pressure distension of the balloon 124.

In other embodiments, a combination is used where a balloon 124 isinflated to be sure that the area distends followed by distention of thestomach using a side port on the magnetic nasogastric tube 114. Thiswill create space for a needle tip to enter the stomach away from thestomach's opposite wall and the needle tip may safely contact themagnetic element 116 on the tip of the magnetic nasogastric tube 114.

In some embodiments, the magnetic element is placed in the geometriccenter of the balloon 124. In some embodiments, the volume of theballoon is approximately 300 cc. In some embodiments, the balloon isfilled with sterile water or other media, including air. In someembodiments, rather than placing the magnetic element in the center ofthe balloon, the balloon may be located behind the magnetic element.Embodiments where the tip of a magnetic nasogastric tube 114 is insidethe balloon 124 and where the tip of the magnetic nasogastric tube 114is outside the balloon 124 are shown in FIG. 12.

As shown in FIG. 13, the medical practitioner then watches as the magnet116 moves away by the distance B from the outside of the balloon 124 tothe magnet 116 in the center if the centering balloon is used. Theinflated balloon 124 lets the operator know that the area being examinedis distensible. In other embodiments, the balloon 124 may be inflatedwhile the tip of the magnetic nasogastric tube 114 remains outside ofthe balloon 124 rather than the balloon 124 inflating around the magnet116. This allows the medical practitioner to know that the area of thestomach is distensible but allows the magnet 116 to remain pressedagainst the gastric mucosa.

Accordingly, in embodiments where a balloon 124 is inflated, the area tobe used for the PEG tube 112 placement is that where the magnet 116 islocated initially and after the balloon 124 is inflated.

FIG. 14A shows a magnetic detection sensor device 118 with a guide path126 for a needle 106 from the outside to be placed into the gastriclumen to touch the magnetic nasogastric tube magnet 116 regardless ofwhether the magnet 116 is against the mucosa or inside a balloon 124.The detector may provide a visual guide to the magnet 116 and also mayprovide a fixed needle guide 126 using a bomb site-like mechanism 128.For example, as illustrated in FIGS. 13 and 14A, the detector identifiesa distance A, 6 cm, from the sensor's needle guide to the tip of themagnet.

Regardless, of what type of indicator and guide the sensor has (e.g., avisual display, a bomb site, a needle guide, etc.), when the newpercutaneous magnetic gastrostomy approach is used, an endoscopic lightshined from the inside is not needed because the medical practitionercan “see” the magnet on the tip of the magnetic nasogastric catheterwith the magnetic detection sensor device. Similarly, when the newpercutaneous magnetic gastrostomy approach is used, the fingerindentation of traditional PEG tube placement is not needed.

In one embodiment and as shown in FIG. 14B, the sensing device 118 cantake the form of a housing that has a folding display screen 122 and abase 130 that carries the magnetic sensors 134 (4 sensors in theillustrated example, located at the corners of the base 130). Centrallylocated between the sensors 134 and passing linearly through the sensingdevice 118 is a vertically oriented guide channel 126, through which aneedle 106 can be inserted into the patient. In an embodiment, the guidechannel 126 corresponds to the center of the “crosshairs” 128 of thedisplay screen 122, such that if the needle 106 is inserted in the guidechannel 126, the needle 106 will penetrate substantially at the locationindicated by the center of the crosshairs 128, which guides the needle106 to the magnet 116 location inside the body.

The sensing device 118 of one embodiment includes a light emittingelement. For example, a plurality (such as a ring or circular pattern)of LED lights 136 or other light source on the underside of the housing,such as shown in FIG. 14C. If the location and depth is determined to beadequate, the ring of LED lights 136 is then activated on the bottom 130of the magnetic sensing device 118 around the guide channel 126. Asshown in the embodiment of FIG. 14C, the exit hole of the guide channel126 is centrally located with respect to the ring of LED lights 136. Thering of lights 136 is of a frequency and/or intensity and/or colorsuited to penetrate the abdominal wall so that the endoscopist may seeit. For example, continuously lit and/or flashing bright LED's may beused if they provide sufficient intensity.

As illustrated in FIG. 14C, the endoscopist may then see the ring oflights 136 (from the sensing device) clearly on the gastric wall andconfirm that this is a suitable area for the PEG tube 112 to beinserted. The gastric wall lights up where the magnet is located. Thisis where the needle 106 will enter the stomach as it goes through theguide channel 126 of the sensor device 118.

An examiner may optionally also use a finger to palpate the abdomen todetermine whether the endoscopist can see the indentation, as in thestandard practice. If everything looks satisfactory, a small incision ismade in the skin, and a needle 106 is inserted into the guide channel126 in the sensing device 118 through the ring of lights 136. Thischannel 126 controls the direction of the needle 106 and assures thatthe direction is orthogonal to the bottom 130 of the sensing device 118and the ring of lights 136.

As shown in FIG. 14D, a guide path on the high resolution screen 122informs the examiner that by directing the needle 106 along the needleguide channel 126 in the center of the ring a lights 136, and to theindicated depth, the needle 106 will enter the gastric lumen in thesubstantially precise location of the magnet 116.

In one embodiment, the needle 106 will enter the gastric lumen withinseveral millimeters or even less distance from the magnet 116. When theneedle 106 is advanced the desired distance, if an endoscopist isobserving, the endoscopist will see the needle 106 enter the stomach viathe wall substantially at the location selected.

The distance from the skin to the gastric wall, which is not known withtraditional PEG techniques, is determined from the outside withsubstantial precision by “seeing” the magnetic element on the magneticnasogastric tube initially and then after the balloon is inflated withthe magnet in the center (in embodiments where a balloon is used). Thatis, the magnetic detection sensor device will provide a medicallyaccurate distance measurement from the sensor to the magnetic element ofthe magnetic nasogastric tube and to the gastric mucosa.

Referring back to FIG. 13, if the distance is measured after the balloon124 is inflated and if the magnet 116 is in the center of the balloon124, the distance from the skin to the gastric mucosa is the distance tothe magnet 116 minus the known distance B from the wall of the balloon124 to the magnet 116. Alternatively the balloon 124 may not be aroundthe magnet 116 but just behind the magnet 116 (towards the mouth) or noballoon may be used and the stomach simply inflated with air or fluidvia the magnetic nasogastric tube 114.

Additional elements in the new approach to placing a magneticnasogastric tube 114 are shown in FIGS. 15 and 16. In FIG. 15, theneedle 106 is inserted in a direction and to a depth as indicated on themagnetic detection sensor device 118. Unlike traditional PEG tubeplacement, where an endoscopist watches the needle 106 enter the stomach100, seeing the needle 106 enter the stomach 100 in one embodiment ofthe new percutaneous magnetic gastrostomy approach is not needed becausethe stomach 100 is inflated using the magnetic nasogastric tube balloon124 (or inflated with a side port of the magnetic nasogastric tube notthe balloon), and the magnetic detection sensor device 118 provides asufficiently accurate location to which a needle 106 will travel.

In FIG. 16, a wire 108 with an element 116 having magnetic properties atits distal end is inserted into the needle 106 and placed very close tothe magnetic element 116 on the magnetic nasogastric catheter 114. Insome embodiments, the wire 108 has a strong magnet 116 secured to itsdistal end. Due to the precision of the magnetic sensor device 118, thewire 108 will be directed to the location of the magnetic element 116 onthe magnetic nasogastric tube 114.

As shown in FIG. 17, when the magnetic elements 116 of the magneticnasogastric tube 114 and the wire 108 are in proximity, the elementswill mutually attract and be coupled together to form a permanent orimpermanent junction. A snare to grasp the wire is not needed becausethe magnet-to-magnet attraction firmly holds the needle wire 108 againstthe magnetic nasogastric tube magnetic element 116. Similarly, theendoscope to pull out the snare holding onto the needle wire is notnecessary because the magnet-to-magnet junction will pull out the needlewire 108 as either the magnetic nasogastric tube 114 is pulled out orthe magnet-to-magnet junction is pulled out of a lumen of the magneticnasogastric tube 114.

In some embodiments the magnetic nasogastric tube and needle wire mayinterlock together to assure that magnets stay coupled as the wire iswithdrawn.

In some embodiments, the magnetic nasogastric tube 114 is formed suchthat the magnetic nasogastric tube 114 or one of its components willconduct a small electric current. As shown in FIG. 18, for example, asmall electric current may be introduced onto the wire 108 or magneticnasogastric tube 114. The small current is then detected by the medicalpractitioner on a current gauge to indicate that the wire 108 and themagnetic nasogastric tube 114 have made physical contact with eachother. The small electrical current (having very low voltage for safety)is just enough to let the medical practitioner know that the two magnetshave touched. In other embodiments, physical contact is indicated byexpressly moving either the wire 108 or the magnetic nasogastric tube114 and noticing a corresponding motion on the other component.

After the magnetic nasogastric tube 114 and the wire 108 have beenjoined, the wire 108 is advanced through the needle 106 or the hole madeby the needle 106 until it passes out through the patient's mouth. Asshown in FIG. 19, the magnetic nasogastric tube 114 may be removed fromthe patient thus pulling the magnet-to-magnet junction with it, or, inalternative embodiments, the magnet-to-magnet junction may also bepulled out via the lumen of the magnetic nasogastric tube 114.

Once the magnet-to-magnet junction is out of the patient's mouth, morewire 108 is pulled through the needle 106 or the hole made by the needle106 if the needle has been backed out. This creates a situation wherethe wire 108 entering the hole made by the needle 106 or through theneedle 106 is now firmly held outside the patient's mouth. If themagnetic nasogastric tube 114 was removed from the patient, then themagnetic nasogastric tube 114 is removed from the wire 108. If the wire108 was passed via a lumen on the magnetic nasogastric tube 114, thenalternate embodiments allow for the magnetic nasogastric tube 114 toeither be removed from the patient or left in place. In someembodiments, the end of the wire 108 extending from the patient's mouthis then attached to the end of the PEG tube. In other embodiments, thePEG tube is placed over the wire 108.

As shown in FIG. 20A, the PEG tube is then pulled into the stomach andup against the gastric mucosa. Sufficient pulling force is used toassure that the bumper of the PEG tube is firmly against the mucosa. Insome embodiments, a separate gauge or metering device 138 is used todetermine that a suitable force is exerted on the wire to appropriatelyseat the PEG tube. Final inspection of the PEG bumper with an endoscopeor x-ray is not needed because a pressure range is given and perhapsmeasured with a small force measuring device 138 to assure that thebumper is snug against the wall. This pressure measurement is likely abetter way to know that the bumper is in the correct place and snug thenis endoscopy. For example, as shown in FIG. 20B, if the bumper looks tobe in the correct place by endoscopy, this means that even though thetube's bumper is on the mucosa, it is still possible that there isexcessive tube between the skin and the outside of the stomach. Byknowing the pressure pulling the bumper against the mucosa, a medicalpractitioner can be sufficiently confident that the bumper is snug andis up against the abdominal wall.

As described in the non-limiting embodiments herein, endoscopy is notnecessary when the new approach to percutaneous magnetic gastrostomyplacement is used. For many similar reasons, x-ray is also notnecessary. For example, the location of the stomach is determined bypassing the magnetic nasogastric tube into the stomach (for instanceapproximately 50 cm from the incisor teeth for a typical adult patient),seeing the magnet in the left upper quadrant (LUQ) of the abdomen, anddetermining the distance from the magnetic element on the magneticnasogastric tube to the skin before and after the stomach is inflated,with or without a balloon.

In the embodiments described above, a PEG tube can be placed safely andquickly into the stomach without either an endoscope or x-ray. With themagnetic detection sensor device, distances are clearly known and thetargeting of the needle to the tip of the magnetic nasogastric tube(with the magnetic element) is facilitated. The medical practitionersubstantially knows the distance to the gastric mucosa, and thesubstantially precise X, Y, Z location of the tip of the magneticnasogastric tube. Further, an embodiment of the magnetic detector has aneedle guide and/or a bomb site type visual guide to enable the medicalpractitioner who is inserting the needle to know where to insert theneedle tip and the depth necessary to contact the magnet on the tip ofthe magnetic nasogastric tube. The magnet-to-magnet attachment removesthe need for a snare and an electrical current detector may be used toassure that contact is made between the two magnetic elements.

B. Additional Methods for Using a Magnetic Nasogastric Tube

Additional non-limiting and non-exhaustive embodiments for the use of amagnetic nasogastric tube for single pass gastrostomy, from the outsideto the inside, are now described with reference to FIGS. 21-28.

In some embodiments, a magnetic nasogastric tube 114 is passed into thestomach. The stomach is inflated, for example with about 300 cc of airand a balloon 124 inflated on the magnetic nasogastric tube 114. In someembodiments, it may not be necessary to use or inflate the gastricballoon 124. Generally, the purpose of the gastric balloon 124 is toprovide some confidence that the tip of the magnetic nasogastriccatheter 114 is freely mobile. The magnetic nasogastric tube 114 is thenpushed against the gastric wall as shown in FIG. 21.

As shown in FIGS. 22 and 23, a magnetic detection sensor device 118 isthen placed on the skin to determine the distance from the skin to themagnet 116 that is on the tip of the magnetic nasogastric tube 114. Ifthis distance is considered suitable by the medical practitioner, forexample, 3 cm, a needle 106 is inserted into the abdominal wall towardsthe magnet 116 on the tip of the magnetic nasogastric tube 114. Theneedle 106 may be guided by a bomb site 128 on the magnetic detectionsensor device 118 and/or a needle guide 126, which provides medicalassurance that the needle 106 is directed to the zone identified by thebomb site 128. In some embodiments, the needle 106 is formed as atrocar. In some embodiments, the needle or trocar is sharp; in someembodiments, the needle or trocar is dull.

FIG. 24 shows another step in the new procedure for single passgastrostomy, from the outside to the inside. Once the needle 106 is inplace, a catheter/introducer 140 is passed from the skin into thestomach. In some embodiments, a wire 108 is passed through the needle106 and the wire 108 guides the introducer 140. In some embodiments, theneedle 106 acts as the wire 108 and guides the introducer 140. The tipof this catheter/introducer 140 is tapered or sharp and is passed to thedepth indicated by the magnetic detection sensor device 118.

Additional steps in the new procedure for single pass gastrostomy, fromthe outside to the inside, are shown in embodiments in FIGS. 25-27. Agastrostomy tube 112 with a rubber or silicon bumper is passed over thesharp introducer 140 until it enters the stomach. The bumper may becompressed as the gastrostomy tube 112 is pushed into position throughthe gastric wall and when the bumper is inside the stomach, thecompressing force is released and the bumper re-assumes its shape as abumper. When the bumper is in position, the sharp or dull trocar,needle, and/or wire placed via the needle are removed. The gastrostomytube 112 may then be pulled back with a suitable pulling force. In someembodiments, a stress measuring gauge 138 is used to measure a suitablepressure on the bumper of the gastrostomy tube 112. The gastrostomy tube112 is then secured in place.

In some embodiments, when the sharp introducer 140 is advanced to thedepth indicated by the magnetic sensor device 18 plus, for example, anadditional 1 cm, the sharp part is removed leaving a cylindricalintroducer with a blunt end over which the gastrostomy catheter isplaced. This would prevent injury from the sharp introducer 140 as thegastrostomy tube 112 is pushed into position. When the tip of thegastrostomy tube 112 and the bumper are in the gastric lumen thecylindrical introducer 140 can be removed. The gastrostomy tube 112 isthen pulled back perhaps using a strain gauge 138 to get the bumpersnugly against the gastric wall.

In some embodiments, for example as shown in FIG. 28, the gastrostomytube 112 with the bumper is passed down the lumen of the introducer 140with the sharp needle/trocar removed. The gastrostomy tube 112 isstretched so that the bumper closes like an umbrella. Once thegastrostomy tube 112 is in the stomach, the stretching force is relaxed,and the gastrostomy tube 112 will re-assume its shape with the bumper.The cylindrical introducer may then be removed and the gastrostomy tubeattached as described herein.

C. A New Magnetic Nasogastric Tube

Additional non-limiting and non-exhaustive embodiments of the new typeof nasogastric (NG) tube, the magnetic nasogastric (MNG) tube 114, andprocedures for using the magnetic nasogastric tube 114 are now describedand shown in FIGS. 29-41. Each of the embodiments described or shown areput forth to present a clearer picture of the magnetic nasogastric tube114 and procedures, but none of the embodiments alone or in anycombination limit the magnetic nasogastric tube and procedures to onlythat which is shown or described. It is noted that particular featuresof the magnetic nasogastric tube 114 and procedures shown and described,along with particular structures, components, or methods, are merelyprovided to present the magnetic nasogastric tube 114 and procedure in aconvenient and understandable manner.

Embodiments of a single pass tube are used and designed as follows. Asshown in FIG. 29, the patient lies supine, and a magnetic nasogastrictube 114 is passed by a medical practitioner approximately 50 cm fromthe incisor teeth down the esophagus into the stomach. The distance issufficient to place the distal end of the magnetic nasogastric tube 114into the stomach of the particular patient. The magnetic nasogastrictube 114 has a magnet 115 at the tip. As shown in FIG. 30, a magneticdetection sensor device 118 is placed over the skin in the LUQ of theabdomen just below the ribs, in a spot suitable for the gastrostomy tubeplacement. As shown in FIG. 31, the stomach 100 is then inflated withair or another substance placed via an optional channel 142 in themagnetic nasogastric tube 114. In some embodiments, a total of about 300cc is passed.

The magnetic nasogastric tube, which was advanced gently through thepatient's mouth and into the stomach, has a magnet 116 on the tip. Themagnetic detection sensor device 118 then is used to detect the presenceof the tip of the magnetic nasogastric tube 114 by locating the tube'smagnet 116.

As shown in FIG. 32, the magnetic detection sensor device 118 can alsotell the current orientation of the tip of the magnetic nasogastric tube114 to determine when the tip of the tube is pointed directionally atthe magnetic detection sensor device 118. The magnetic nasogastric tube114 is then gently manipulated and the magnetic detection sensor device118 quantifies the distance from the magnetic detector 118 to the tip ofthe tube 114. At this stage of the procedure, the medical practitionersubstantially knows the location of the tip of the magnetic nasogastrictube 114, the orientation of the magnetic nasogastric tube 114, and thedistance from the skin to the tip of the tube 114.

Next, as shown in FIG. 33, a balloon 124, may be inflated. In someembodiments, the balloon is formed such that it is attached to themagnetic nasogastric tube 113 just above the magnet 116 and the airinflation port 142. This balloon 124 may have, for example, a volume ofabout 100 cc. If the balloon 124 inflates easily, the medicalpractitioner sufficiently knows that the tip of the magnetic nasogastrictube is in a free portion of the stomach.

The continued inflation of the stomach, to a volume of 300 cc forexample, may also indicate that the stomach is the site of the distalend of the magnetic nasogastric tube 114. In some embodiments, it maynot be necessary to use a balloon on the end of the magnetic nasogastrictube 114.

In some embodiments, the magnetic nasogastric tube 114 is formed suchthat a sharp needle 106 embedded in the tip of the magnetic nasogastrictube 114 may be advanced or retracted at a suitable time by the medicalpractitioner. For example, FIG. 34 shows that if the distance,orientation of the tip, and location on the abdominal wall issatisfactory (for example 3 cm, pointing towards the sensor, LUQ 4 cmbelow rib margin) and the magnetic nasogastric tube 114 is pushed gentlyagainst the gastric mucosa, then a special plunger 144 on the proximalend (i.e., the end still outside the patient) of the magneticnasogastric tube 114 may be advanced and a sharp needle 106 advances outof the distal tip of the magnetic nasogastric catheter 114, movesthrough the gastric and abdominal walls, and exits the skin where thedetector 118 noted the magnetic signal.

In some embodiments, as shown in FIG. 35, the magnet 116 may be placedon the tip of the needle 106 or the needle 106 may be formed from amaterial having magnetic properties so the examiner can watch the needle106 as it exits the magnetic nasogastric tube 114 and moves towards thesensor 118 from the inside of the stomach. In some embodiments, theneedle is a trocar.

FIG. 36 shows that the sharp tip may then be covered for safety and theneedle pulled out of the skin. In some embodiments, when the needle 106is pulled, it will thereby pull more of the wire 108 that was used as aplunger 144 to push the needle 106. In other embodiments, a separatewire 108 may be advanced down the magnetic nasogastric tube 114 andeither exit the lumen of the needle 106 or be funneled through a lumenin the trocar.

Another step is shown in FIG. 37 where the plunger advancer 144 and thecovering tube 146 part of the magnetic nasogastric tube 114 is removedfrom the patient leaving behind the wire 108 and the sharp needle/trocar106. This leaves the wire from the skin of the abdomen to the mouth.

FIG. 38 shows a wire 108 attached to a tapered end of a gastrostomy tube112. In some embodiments, the wire 108 is then manually attached to thesharp, tapered introducer tip of a gastrostomy tube 112; in otherembodiments, the gastrostomy tube 112 is attached during manufacture. Instill other embodiments, as shown in FIG. 39, the tapered introducer 140of the gastrostomy tube 112 is placed over the wire 108 thereby usingthe wire 108 as a guide wire.

In some embodiments where the gastrostomy tube is attached to the wire,FIG. 40 shows that the PEG tube 112 is then pulled through the mouth,down the esophagus, into the stomach, and then through the gastric andabdominal walls into a suitable position where it is secured. In someembodiments, a strain gauge 138 determines the proper pulling force forthe tube 112. In these embodiments, the wire is removed from the patientas the tube is pulled into the stomach and through the abdominal wall.

Another embodiment is shown in FIG. 41 in situations where thegastrostomy tube 112 is threaded on the wire 108. In these situations, a“pusher tube” 148 is also threaded on the wire and the gastrostomy tubeis pushed down the mouth, esophagus, and stomach and out over the wireuntil it exits the abdominal wall and can then be pulled into position,quantified in terms of pull, and then secured. In this instance thepusher tube 148 is subsequently removed back over the guide wire 108. Insome embodiments, the guide wire 108 can be removed with the pusher 148or after the pusher 148 is removed. The guide wire 108 can be removedvia the mouth or via the skin of the abdomen, by pulling it through thegastrostomy tube 112.

In some other gastrostomy tube placement procedures, the tube 112 ispressed from the outside of the abdomen, through a hole in the abdomen,and into the stomach. In some cases, the end of the gastrostomy tube 112may problematically not be fully passed into the stomach. However, inthe embodiments described herein, where the gastrostomy tube 112 ispulled or pushed via the mouth into the stomach, the medicalpractitioner can be medically confident that the bumper is in thestomach and not in the tissue between the stomach wall and the skinbecause the bumper is pulled into the stomach via the mouth instead ofbeing pushed into the stomach from the outside of the abdominal wall.

D. Additional Embodiments of a Magnetic Nasogastric Tube

Additional non-limiting and non-exhaustive embodiments using the newequipment and new procedures are shown in FIGS. 42-50 and describedbelow. In some embodiments, when a gastrostomy guide wire is to bepassed from the inside of the stomach through the gastric and abdominalwalls to the outside, some additional features of the equipment orprocedure may be used.

For example, an embodiment is shown in FIG. 42 where a balloon 124 helpsmaintain the orientation of the tip of the magnetic nasogastric tube 114so that the needle 106 will exit in the direction desired and selectedfrom the outside.

In another embodiment, shown in FIG. 43, a tripod 150, which opens whenextended from the catheter 114, may keep the tip of the magneticnasogastric tube 114 orthogonal to the mucosa.

Another embodiment of a magnetic nasogastric tube 114 is shown in FIG.44 where the end of the magnetic nasogastric tube 114 may becontrollable with guide wires 152 to move the tip or with a small builtin curvature and torque stability so that rotation of the tube 114 willmove the tip in a different direction. In some embodiments, an indexingmark on the tube, visible at the patient's mouth, allows the orientationof the tube in the patient's stomach to be known.

FIG. 45 shows an embodiment where the magnetic nasogastric tube 114 willbe somewhat stiff so it is controllable and so that it is not “floppy.”

This is important for orientation and so that the needle 106 can beextended from the tip of the tube 114 and through the wall of thestomach and abdomen.

It is shown in FIG. 46 that while unnecessary for the proceduresdescribed herein, an endoscope 154 may be used in some embodiments tofacilitate placement of the gastrostomy tube 112. For example, anendoscope 154 can pick a spot on the wall and hold in the correctdirection the end of the magnetic nasogastric tube 114, when themagnetic nasogastric tube 114 is passed via one of the endoscopechannels. In this way the needle 106 may be substantially aimed at thesite selected from the outside with the aid of a magnetic detectionsensor device 118. The endoscope 154 can also be pressed against themucosa and aimed in the desired direction.

A magnetic element 116 may be placed on the end of the needle 106 or onthe end of the magnetic nasogastric catheter 114 used to pass the needle106. This catheter 114 is thus also is useful to protect the patientfrom the needle's sharp end as the needle 106 is passed through theesophagus into the stomach or to protect the endoscope 154 as the needle106 is passed via the biopsy channel of the endoscope 154.

An embodiment is shown in FIG. 47 where a controllable guide tubeinstrument 156 has some of the features of an endoscope 154, but whichis not an endoscope 154. The controllable guide tube instrument 156 maybe used to guide the magnetic nasogastric tube 114 having a magneticelement 116 and in some embodiments, a needle 106. This new instrument156 can be similar to an endoscope 154 but without suction, withoutoptics, without irrigation, and without light. It can be a somewhatstiff tube with armor; flexible, and with a channel 164 for the magneticnasogastric tube 114.

This controllable guide tube 156 can have a sheath 162 and a removablechannel 164 so that when the sheath 162 and the channel 164 are removedand replaced, the next patient has a sterile guide tube 156 free ofcontamination from the previous patient. In addition or in alternativeto the features stated above, some embodiments of the controllable guidetube 156 may have an optional stabilizing balloon 124.

Embodiments of the controllable guide tube instrument 156 would be farless expensive than an endoscope 154, and in some embodiments this tube156 might be reusable using a sheath 162. In some embodiments, thecontrollable guide tube instrument 156 might be disposable and made outof simple materials at low cost. In some embodiments, the guide tube 156can also be made out of materials that can be cleaned and thensterilized with vapor, liquid, or steam sterilization.

FIGS. 48 and 49 show other embodiments of a magnetic nasogastric tube114 that have a balloon 124 attached. In some situations, it may beuseful to use a very large volume balloon 124 to stabilize the tip ofthe magnetic nasogastric tube 114 by filling up the volume of thestomach. This may help to provide stability as the needle 106 is passedthrough the gastric wall and abdominal wall to the outside of the skin.In other situations, the medical practitioner may have increasedassurance that the area selected is expandable and free of otherstructures, by using a magnetic nasogastric tube 114 having a balloon124 that includes an internal structure 166 formed so as to assure thatthe balloon 124 inflates uniformly in all directions and with part ofthe structure located in a known and suitable location relative to theballoon 124.

In some embodiments, as shown in FIG. 50 for example, if a magneticnasogastric catheter 114 is used to pass a needle 106 from the inside ofthe stomach to the outside of the abdominal wall, it may be useful touse a catheter 114 which is flexible when passed into the patient'sbody, but when in position to pierce the gastric and abdominal walls,the catheter 114 can be made rigid. In some embodiments, the magneticnasogastric catheter 114 is formed with the use of wires 168 embedded inthe tube's walls. These wires 166 may further assist in keeping theorientation of the tip of the catheter 114 and facilitating passing theneedle 106 through the gastric and abdominal walls to the outside of theskin.

E. Embodiments of a Controllable Magnetic Nasogastric Tube

Additional non-limiting and non-exhaustive embodiments of a new type ofnasogastric (NG) tube, a controllable magnetic nasogastrostomy (MNG)tube, and procedures for using the controllable magnetic nasogastrictube 114 are now described and illustrated in FIGS. 51-56.

In some embodiments, as shown in FIG. 51, the controllable magneticnasogastric tube 114 will have one or more of the features of a diameterabout 8 mm or 24 French, a flexible but not floppy constitution, aformation which is stable with regards to torque such that the tube maybe operatively turned from one end and maintain the same turningcomponent throughout a suitable length of the tube, a channel or groove170 for a guide wire embedded in the controllable magnetic nasogastrictube or formed on the side of the controllable magnetic nasogastric tube114, a soft introducer tip 172, an exit for the channel at very tip ofthe controllable magnetic nasogastric tube, an exit for the channel thatis parallel with the soft introducer tip, a biopsy channel to introducea wire or gas, and a suction channel to remove gas.

FIG. 52 shows additional features of a controllable magnetic nasogastrictube 114, for example, a control 174 for bending the tip in 1 to 4directions to 90 degrees or 180 degrees. The control handle is formed onthe proximal end, which remains outside the patient. In someembodiments, the control handle at the proximal end of the controllablemagnetic nasogastric tube 114, which is outside the patient andmanipulable by a medical practitioner, may have a visual and/or tactilequeue to indicate the direction of the bend.

FIG. 53 shows additional features of a controllable magnetic nasogastrictube 114, for example, a slide plunger 176 which may attach to a guidewire 108 and be used to advance a needle 106 formed or attached on thetip of the guide wire 108 through the gastric and abdominal walls. Theplunger 176 can then be released from the guide wire 108 as thecontrollable magnetic nasogastric tube 114 is removed.

The controllable magnetic nasogastric tube 114 may be removed after thewire 108 is secured outside the skin of the patient's abdomen. The guidewire 108 may be released by backing the controllable magneticnasogastric tube 114 over the guide wire and out of the patient or byreleasing the guide wire 108 from the channel or groove in the side ofthe controllable magnetic nasogastric tube and then backing out thecontrollable magnetic nasogastric tube.

The controllable magnetic nasogastric tube 114 may be formed with one ormore devices or mechanisms to pass air or another medium of inflationinto the patient. Several embodiments are shown in FIG. 54. For example,some embodiments of the controllable magnetic nasogastric tube 114 mayhave an air insufflation port 170. Some embodiments may have a valve forputting in air, and in some embodiments, a valve to prevent too much airor other medium and/or too much pressure in the site where thecontrollable magnetic nasogastric tube is placed. Other embodiments mayuse a simple bag 180 or a syringe 178 instead of a pump 182. Someembodiments may have measuring devices for gauging volume and/orpressure of the medium passed into the body through the controllablemagnetic nasogastric tube 114.

FIG. 55 shows an embodiment of a controllable magnetic nasogastric tube114 having a smooth, gentle, soft tip 184 making this tube easy tointroduce into a patient's body.

FIG. 56 shows a controllable magnetic nasogastric tube 114 having amagnetic element 116 on the tip; other embodiments may form a magneticelement in the tip of a soft rubber introducer, which may be passed viathe magnetic nasogastric tube.

The multitude of features of the new controllable magnetic nasogastrictube described above provide many benefits that are not found in otherdevices or methods of performing percutaneous gastrostomy. For example,during a procedure, the controllable magnetic nasogastric tube has noneed for light or vision in its distal end, and additionally, no needfor a water source to wash the tip while the controllable magneticnasogastric tube is inserted into a patient's body. Example embodimentsof the new controllable magnetic nasogastric tube may be disposable ormay be reusable. If the controllable magnetic nasogastric tube isreusable, it may be covered with a sheath that covers the channel intowhich the needle and guide wire are inserted. In these embodiments, thechannel may be removed along with the sheath and both are replaced aftereach new procedure is performed on a patient so that each subsequentpatient has a totally new or totally uncontaminated controllablemagnetic nasogastric tube. In some embodiments, the sheath may be looseor tight, and if the sheath is tight, the technique for its use mayinvolve a roll-up method of placement or an inflation method.

In some embodiments, a reusable controllable magnetic nasogastric tubemay be formed from material that can be gas sterilized. Embodiments ofthe controllable magnetic nasogastric tube design are relatively simplecompared to traditional endoscopic or similar devices and the newcontrollable magnetic nasogastric tube may be formed with few if anyniches or inaccessible recesses. Accordingly, embodiments of the newcontrollable magnetic nasogastric tube are conducive to wash down andgas sterilization so that a sheath may not be necessary. In someembodiments, the design of the controllable magnetic nasogastric tubemay permit the device to be sterilized in an autoclave, just likesurgical instruments.

F. Additional Embodiments of Placing a Peg Tube

As described herein, embodiments having a magnet locator showing asubstantially exact location of a magnet at a selected location on thestomach wall may now be used in medical practice. The distance from theskin to the magnet is determined with substantial precision. When usedwith endoscopic techniques, the placement of medical devices isimproved. For example, if the distance from the skin to the magnet isexcessive, an endoscopist may move the magnet onto another area of thegastric wall and use the external sensing device to find an area closerto the skin, which is better suited for placement of a PEG tube.Alternatively, the procedure may be considered too high risk because ofexcessive depth (e.g., possibly caused by adjacent liver or colon), andthe procedure may be canceled because of the risk of hitting adjacentorgans.

In another example, an indentation is no longer the only way that theendoscopist can determine whether a needle will enter the area selected.Instead, a ring of bright external lights on the sensing device may beseen inside the stomach via the endoscope. This will inform anendoscopist that if the guide channel is used, it will place the needlein the area selected.

In some embodiments, the lights on the sensing device outside thepatient may be located on the tip of a cone or mound. In this way thecone is pressed against the abdomen very much like the standard methodof using the finger of the person on the outside, then the lights areturned on and the substantially exact position of the planned insertionof the needle can be clearly seen from the inside by both the positionof the indentation of the mound and the ring of lights. An examiner maystill use the indentation but it is no longer the sole way toapproximate where a needle will enter the gastric lumen.

In some medical procedures, a primary examiner and an assistant examinerwork together to place a medical device in a living body. The use of themagnetic techniques described herein provide the assistant examiner withmore knowledge about the desired location of the entrance to the gastricwall. The X and Y location of the magnet is clear (e.g., less than 1 mmprecision), and the depth of the magnet is also clear, so the correctdepth of needle is selected. This eliminates using more needle lengththan needed, especially if the target is missed. Accordingly, multipleexcessively long insertions are no longer needed.

The magnet sensing system also has optional sensory aids (e.g., graphicindicators, sounds, etc), which inform the outside examiner that if aneedle is inserted down the guide channel in the sensing device, it willgo in the direction of the magnet. The sensory aids on the magnetsensing device may display the position and depth of the magnet, and mayalso provide a graphic guide path to inform the assistant examiner thatif the needle is in the guide channel, the tip will go in the direction(in three dimensional space, using Cartesian coordinates X, Y and Z, forexample) of the magnet. The length of needle needed is now known withsubstantial precision as well as the direction the needle should go tohit the magnet. The sensing device can be moved to place the guide pathfor the needle onto the magnet target.

The above embodiments relate to a new way to place a tube into the body,such as a PEG tube using magnetic and optical (light) guidance. A tubeis placed inside the body with a magnet, localized where the tube andmagnet are (e.g., with endoscopy, x-ray, ultrasound, etc.), then amagnet sensing device is used to locate the magnet inside the body andto advance a needle with a central wire, which supports placement oftubes for drainage, feeding, decompression, etc.

Additional embodiments are illustrated in FIGS. 57-66 and described indetail by way of the non-exhaustive and non-limiting examples herein. Inparticular, a method is shown for placing a tube from the inside bymaking the needle insertion from inside of the stomach. A PEG tube isused as an example, but small bowel tubes, colostomy tubes, etc., mayalso be possible with this method.

FIG. 57 shows an endoscope 154 placed into the stomach 100. An area isselected which the endoscopist believes would be suitable for the buttonseal on the PEG tube inside the stomach. A catheter 114 having a magnet116 at its distal end is then advanced from the tip of the endoscope154, under direct vision, to the area of the gastric mucosa selected forthe PEG tube placement 186. In this embodiment, the endoscopist iscareful to note the position of the pylorus 102 so as to avoid injury.

FIG. 58 shows how an external magnet sensing device 118 may be used tolocate the position of the magnet 116 from the anterior abdominal wallside. The device 118 locates the magnet 116 in three-dimensional spaceand determines the distance from the magnet to the skin surface. In oneembodiment, the sensing device 118 of FIG. 58 can use similar techniquesand components as otherwise described herein for locating and displayingthe position, orientation, depth, etc., of a magnet 116 being sensed.

FIG. 59 shows how an assistant may then use light or a digital palpation104 to confirm that the spot where the magnet is seen on the detector isbelow the rib cage and in a good position on the anterior abdominal wallfor the PEG tube to exit the patient. Light from the inside (endoscopeor bright light catheter) or from the outside (bright light such as anLED on the detector or as a free standing light) can confirm thereasonable position inside and outside for the PEG location.

FIGS. 60-63 show that when the site has been selected from the insideand outside, a catheter 140 held by an endoscope 154 may be used to pusha needle 106 from the gastric lumen to the skin. This can be a verythin, fine needle or a thicker needle.

The needle 106 of FIG. 60 may be still except for advancing, or theneedle may rotate, such as shown in FIG. 61. The needle 106 may advancefrom the endoscope 154, from the catheter 140, or from its own carryingovertube 188, such as shown in FIGS. 60-62.

The overtube 188 may be quiet or may have a function in which the tipretracts thereby stabilizing the tip so that the direction of the needle106 can be controlled. This arrangement also covers the tip of the sharpcatheter 140, preventing injury to the gastric or esophageal wall priorto the time when the operator wants to advance the needle 106. It willalso protect the inside of the catheter 140 used to guide the needle tipinto the stomach, for example the biopsy channel of the endoscope 154.

FIG. 64 shows an embodiment wherein the tip of a cutting needle 106(rotating or not) may be the magnet 116 itself. In this way the externalmagnet sensing device 118 may watch the path of the tip of the needle106 as a three-dimensional projection on the screen 122.

In another embodiment, the magnet 116 may be located on adevice/catheter separate from the needle. Thus, after a first magneticnasogastric catheter 114 having the magnetic tip 116 is used to locatean insertion point in the gastric wall, the first catheter 114 iswithdrawn and a second catheter 140 having the needle 106 at its tip isused to insert the needle 106 through the gastric wall. A double lumencatheter may allow for the magnet tip catheter to be inserted and, whenposition is selected, a needle tip catheter is extended out of thesecond channel.

FIG. 65 shows that when the needle 106 exits the skin, it is pulled outmanually and additional cable 108 is advanced through the patient'smouth. The proximal end (towards the patient's mouth) is then attachedto the loop on the end of a PEG tube 112.

FIG. 66 shows that the PEG tube 112 is then pulled through the skin siteuntil the pointed end emerges, and the PEG 112 is then placed intoposition with mild pressure.

One advantage of the approach proposed in the embodiments of FIGS. 57-66is that it may be faster because the endoscopist does not have to grabthe wire coming out of the needle in the gastric lumen. Anotheradvantage is that the endoscopist knows with substantial precision wherethe PEG tube will be in the stomach, and the assistant knows withsubstantial precision where the PEG tube will be located on the anteriorgastric wall. Additional advantages are improved accuracy, knowledge ofthe distance from the gastric wall to the skin, an ability to watch theprogress of the needle tip, and fewer potential complications fromhaving to grasp and hold the wire in the gastric lumen. Accordingly,this new procedure may be easier, faster, and safer than otherapproaches.

It is also clear from the description herein of non-limiting andnon-exhaustive embodiments that a far safer method is provided forselecting a spot for PEG tube placement and insertion of a needle toaccomplish the safe insertion, which reduces several risks to thepatient, including, for example, not knowing where the selected site onthe gastric wall contacts the skin on the outside, not knowing where theneedle placed through the skin will enter into the stomach, and notknowing the direction that the needle should be directed to hit theselected gastric wall location. Another example is not knowing thedistance from skin to the gastric wall, and therefore not knowing thelength of needle to be inserted into the patient. Using excessive lengthmay cause injury to adjacent organs, which would not be touched ifexcessive length were not used.

In addition to solutions and advantages already described, theembodiments can be more accurate, faster, have a higher success rate,and have a lower complication rate than with previous PEG placementprocedures. The examiners know substantially where the needle must go tohit the target on the gastric wall. Increased precision in guidanceincreases the examiner's confidence and speeds the minimally invasiveprocedure. Further, less procedure time means more safety for thepatient and reduced cost.

G. Additional Embodiments of Placing a Medical Devices

In addition to the examples for placing a PEG tube in a stomach, othermedical devices can be placed in other locations of a living body. Thetarget organ or space may be fairly small and it may be very difficultor impossible to safely place a needle into it from the outside of apatient through the skin. However, with the magnet locating systemdescribed herein, an external needle can be accurately and safely guidedto the magnet already placed into the organ, and a connection createdbetween the outside of the patient and the internal magnetic device. Ifthe tip of the device is already in the space and must exit, an examinercan be reasonably sure that the tract or device will connect from theskin to the target space or organ.

The following list is a non-exhaustive, non-limiting list ofapplications where embodiments of the present invention may be employedfor many organs for drainage, feeding, antibiotic infusion, etc. Forexample: Place PEG tube into the stomach; Place Percutaneous EndoscopicJejunostomy (PEJ) tube into small bowel; Place tube into the colon(cecum, hep flex, splenic flex); Place tube into sigmoid colon; Placetube into renal calyx; Place tube into bladder; Place tube into abnormalcollection of pus, fluid, cyst, etc.; Place tube into chest wall withair or fluid or purulence; Place tube into artery; Place tube into vein;Place tube into heart (RA, RV, LA, LV), which may be way to rapidlyplace pacer or defibrillation wire into RV or LV as one can bereasonably sure where the inside tip of the needle or wire is located,and if the magnet is in the RV and is advanced through the muscle to theskin, one can be reasonably sure it is in contact with the RV; Placetube from one vessel into another, such as artery to vein, artery toartery, and vein to vein; Place arteriovenous shunts; Place portocavalshunt; and Use to place diagnostic or therapeutic devices at laparoscopyor thoracoscopy. It is thus shown that the various embodiments provide anew, minimally invasive system, device, and method to place a medicaldevice into a small or difficult to access space.

In one application, the techniques and devices described herein areuseful for placing a medical device into an intestine, e.g., a smallintestine. The small intestine in a body is typically loosely packedsuch that when pressure is applied, the intestine moves. Accordingly,penetrating the small intestine with a needle, catheter, or othermedical device can be an elusive task for a medical practitioner.

Among the techniques described herein, additional embodiments are alsouseful for placing a medical device in the intestine. For example, amagnetic tipped wire may first be inserted into the intestine. Next, amagnetic detection sensor device may be used to detect, with substantialprecision, the three dimensional location of the magnet. In oneembodiment, the magnetic tipped wire has a particularly shaped magnet.Thus, when a magnet-tipped needle or other medical device is insertedthrough the body, via a guide channel in the magnetic detection sensordevice, the attraction between the device and the magnetic tipped wirecauses penetration of the intestine, regardless of the intestine'smobility.

In another embodiment, the magnetic tipped wire has additionalstructural elements to clamp the intestine in place. For example, anexpandable tripod or other shaped structure may be released tosufficiently immobilize the intestine for penetration by the needle.

In still another embodiment, after the magnetic tipped wire is locatedwith the magnetic detection sensor device, a clamping device is insertedthrough the magnetic detection sensor device and firmly clamps theintestine from the outside. Subsequently, the now immobilized intestinecan be pierced with the needle or other medical device.

The systems, devices, and methods described herein in non-limiting andnon-exhaustive embodiments for PEG placement may also be used in otherembodiments for other diagnostic and therapeutic interventions. Inaddition, in each of the embodiments described above and below, it isrecognized that several non-limiting and non-exhaustive variations arepossible.

For example, one variation recognizes that some magnet sensing devicesmay not have lights. Other variations may have lights on a cone, smallmound, hill, protrusion, or other suitably shaped device so pushes incan more readily be seen inside. In variations, the lights may be placedin a location or pattern suitable to a particular use. For example, themagnet sensing device may have lights in a ring so the endoscopist cansee the light coming from the outside. In another example, the lightsmay be formed at the apex of a protrusion.

In another embodiment, the system may provide substantially preciselocalization of a desired target from the outside of the patient andthen guide the diagnostic or therapeutic catheter to this location(e.g., using X, Y, Z Cartesian coordinates) with substantial precision.The system may also provide direction and a guide path displayed on thescreen of the magnet sensing device.

FIG. 67 shows another embodiment using magnets and possibly lights, asin the PEG tube placement embodiment described above. In FIG. 66, acolostomy tube placement into the colon is shown. A colonoscope 190 isused to guide a device having a magnet 116 into the patient's colon 192.A magnetic sensing device 118 informs the practitioner of the locationof the magnet from the outside.

FIG. 68 shows another embodiment where a cystoscope 194 places a magnet116 on the bladder wall, and the system is used to pass a catheter 140through the skin into the bladder. A light may be used to predict wherethe catheter 140 will enter the bladder, and the cystoscope 194 imagedetermines whether this will be an acceptable spot for the catheter 140.

FIG. 69 shows another embodiment where a laparoscope 198 is used toguide substantially precise entrance of additional catheters 140 andneedles 106. At laparoscopy under direct vision, a target is selectedfor an additional tube 140. This spot may be one free of blood vesselsto avoid bleeding, or free of adhesions to avoid complications withadhesions. A magnet 116 in a catheter 140 marks this spot in thepatient's abdominal cavity. The external magnetic sensing device 118locates the magnet (at the target) and gives a guide path 126 (directionand depth) as to how to get to the magnetic marker through the skin tothe target.

FIG. 70 shows another embodiment where a magnet can be placed using acatheter under x-ray guidance. The magnet 116 can then be located andthe system used to guide a percutaneous (e.g., vascular) catheter 202 tothe spot. In this embodiment, a catheter 202 with a magnet 116 may bepassed into an artery or vein (e.g., under x-ray, CT, MRI or ultrasoundguidance) into the target lesion or organ.

FIG. 71 shows another embodiment where the substantially preciselocation of a magnet 116 is determined with a magnet sensing device 118,which also gives a substantially precise guide path 126 to pass a needle106 or other catheter to the location of the magnet 116.

For example if a tumor 204 in the liver is the problem, a magnetictipped catheter can be inserted into a vein and then into the tumor 204under x-ray guidance. The magnet sensing device 118 is then used todetermine with substantial precision the location of the tumor 204 (withthe magnetic tipped catheter in position). A magnet sensing device 118and guide path 126 directs the examiner to the proper depth of thetarget and the X, Y, Z location, such as represented in FIG. 72.

A catheter may then be placed (e.g., through the skin or by endoscope orlaparoscope) to get the catheter (or needle) to the magnet's location.Next, the magnet can be removed, and diagnosis is obtained via thecatheter (e.g., aspiration, biopsy, brushing, etc.) or therapy isperformed (e.g., heating, cooling, mechanical removal of tissue, RFablation mono or bipolar, use of radiation catheter to perform RT,etc.). A catheter can also be placed and used for infusions of therapysuch as cryotherapy, radiation therapy using a radiation emitting smallcatheter, infusion of chemotherapy, etc.

Accordingly, anywhere a catheter or needle can be placed; a magnet on acatheter can be inserted through a needle or catheter and then locatedto facilitate diagnosis and therapy. In a manner similar to that forplacement of a PEG tube as described above, it may be possible to placea tube into a target using imaging guidance (x-ray, CT, MRI, ultrasound,PET, with or without contrast agents), with a magnet on the tip of thetube so its substantially precise location can be found from outside thebody. Once the tube is placed, a second needle-tipped wire or cathetercould be inserted through the first tube and advanced from the target tothe outside of the patient or to an adjacent organ to facilitatepositioning of a diagnostic or therapeutic device.

FIG. 73 shows another embodiment where a magnet sensing device 118 maybe separated after a needle or wire is placed into the target. FIG. 73shows one embodiment where a “release channel” 208 is used. The releasechannel 208 may be permanently open or may be temporarily closed duringguidance and opened to release the magnet sensing device 118. Forinstance, a removable plug 206 may be provided to temporarily keep therelease channel 208 closed during guidance, and then removed to releasethe magnet sensing device 118. In embodiments with a release mechanism,the reusable magnet sensing device 118 may still be covered by a sterilesheath 162.

From the foregoing it will be appreciated that, although specificembodiments have been described herein for purposes of illustration,various modifications may be made without deviating from the spirit andscope of the invention. Accordingly, the invention is not limited bythis disclosure.

The various embodiments described above can be combined to providefurther embodiments. All of the U.S. patents, U.S. patent applicationpublications, U.S. patent applications, foreign patents, foreign patentapplications and non-patent publications referred to in thisspecification and/or listed in the Application Data Sheet, areincorporated herein by reference, in their entirety. Aspects of theembodiments can be modified, if necessary to employ concepts of thevarious patents, applications and publications to provide yet furtherembodiments.

These and other changes can be made to the embodiments in light of theabove-detailed description. In general, in the following claims, theterms used should not be construed to limit the claims to the specificembodiments disclosed in the specification and the claims, but should beconstrued to include all possible embodiments along with the full scopeof equivalents to which such claims are entitled. Accordingly, theclaims are not limited by the disclosure.

What is claimed is:
 1. A medical device system, comprising: a needlehaving a tip including a permanent magnet; and a magnet sensing deviceincluding a plurality of sensors configured to detect the magnetic fieldof the permanent magnet, the magnet sensing device operable to localizea position of the permanent magnet relative to the magnet sensing deviceand to indicate a path of the needle on a display.
 2. The systemaccording to claim 1, wherein the path is a three-dimensionalprojection.
 3. The system according to claim 1, wherein the magnetsensing device includes an audible indicator operable to provide arepresentation of the position of the permanent magnet relative to themagnet sensing device.
 4. The system according to claim 1, furthercomprising a light emitting element coupled to the magnet sensingdevice.
 5. The system according to claim 4, wherein the light emittingelement is configured to provide visible light with sufficientbrightness to penetrate tissue of a body such that the light is visiblefrom a location inside the body.
 6. The system according to claim 4,wherein the magnet sensing device and the light emitting element are inphysically separable housings.
 7. The system according to claim 4,wherein the light emitting element is positioned on a face of the magnetsensing device, the light emitting element operable to confirm theposition of the permanent magnet relative to the magnet sensing device.